Question

输入文件DATA1.txt将包含7行，每行包含一个正整数，用于描述每种类型的糖果数量。输出文件OUT1.txt将包含与输入的数字相同的星数。即：输入DATA1.txt将显示：

输出OUT1.txt将显示：

12: ************
8: ********
10: **********
5: *****
20: ********************
3: ***
7: *******

我想已经有一个名为DATA1的文本文件已经创建了7个数字。我希望程序读取它（使用fileRead类）并创建一个名为OUT1的新文本文件，其中包含这些数字和与它们对应的*（使用fileWrite类）。我想一起摆脱用户输入。我该如何修改这个程序？

这是我写的代码：

import javax.swing.*;
import java.io.*;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class CandyLand{
   public static void main(String str[]){
      int num1,num2,num3,num4,num5,num6,num7;

      String input1 = JOptionPane.showInputDialog("Please, enter the number of candies in the first pile");
      num1 = Integer.parseInt(input1);
      String input2 = JOptionPane.showInputDialog("Please, enter the number of candies in the second pile");
      num2 = Integer.parseInt(input2);
      String input3 = JOptionPane.showInputDialog("Please, enter the number of candies in the third pile");
      num3 = Integer.parseInt(input3);
      String input4 = JOptionPane.showInputDialog("Please, enter the number of candies in the fourth pile");
      num4 = Integer.parseInt(input4);
      String input5 = JOptionPane.showInputDialog("Please, enter the number of candies in the fifth pile");
      num5 = Integer.parseInt(input5);
      String input6 = JOptionPane.showInputDialog("Please, enter the number of candies in the sixth pile");
      num6 = Integer.parseInt(input6);
      String input7 = JOptionPane.showInputDialog("Please, enter the number of candies in the seventh pile");
      num7 = Integer.parseInt(input7);

      String fileName = JOptionPane.showInputDialog("Please, enter the name of the file");
      try{
         DataOutput f = new DataOutputStream(new FileOutputStream(fileName + ".txt"));
         f.writeBytes(String.valueOf(num1));
         f.writeBytes("\r\n");
         f.writeBytes(String.valueOf(num2));
         f.writeBytes("\r\n");
         f.writeBytes(String.valueOf(num3));
         f.writeBytes("\r\n");
         f.writeBytes(String.valueOf(num4));
         f.writeBytes("\r\n");
         f.writeBytes(String.valueOf(num5));
         f.writeBytes("\r\n");
         f.writeBytes(String.valueOf(num6));
         f.writeBytes("\r\n");
         f.writeBytes(String.valueOf(num7));
      }
      catch(Exception e){
         String msg = e.toString();
         System.out.println(msg);
      }

      Scanner file = null;
      ArrayList<Integer> list = new ArrayList<Integer>();

      try {
        //You should be reading from the first file you created, not OUT1.txt
         file = new Scanner(new File(fileName + ".txt"));
      } 
      catch (FileNotFoundException e) {
         e.printStackTrace();
      }

      while(file.hasNext()){
         if (file.hasNextInt())
            list.add(file.nextInt());
         else file.next();
      }
      try {
        //Instead using System.out.println, use DataOutput like you were using before
         DataOutput f2 = new DataOutputStream(new FileOutputStream("OUT1.txt"));
         for (Integer j: list){
            f2.writeBytes(j + ": ");
            for(int i=1; i<=j; i++){
               f2.writeBytes("* ");
            }
            f2.writeBytes("\r\n");
         }
      }
      catch(Exception e){
         e.printStackTrace();
      }
   }
}

这些是我提到的方式：

写文件：

import javax.swing.*;
import java.io.*;
class fileWrite{
    public static void main(String str[]){
        String fileName = JOptionPane.showInputDialog("Please, enter the name of the output file");
        try{
            DataOutput f = new DataOutputStream(new FileOutputStream(fileName + ".txt"));
            f.writeBytes("Teacher: Hello");
            f.writeBytes("Student: Hi");
            f.writeBytes("Teacher: Why are you late?");
            f.writeBytes("Student: I slept in");
        }
        catch(Exception e){
            String msg = e.toString();
            System.out.println(msg);
        }
    }
}

阅读文件：

import javax.swing.*;
import java.io.*;
class fileRead{
    public static void main(String str[]){
        String fileName = JOptionPane.showInputDialog("Enter the name of the file I need to read from");
        try{
            DataInput f = new DataInputStream(new FileInputStream (fileName + ".txt"));
            String txt = f.readLine();
            while(txt != null){
                System.out.println(txt);
                txt = f.readLine();
            }
        }
        catch (Exception e){
            String msg = e.toString();
            System.out.println(msg);
        }
    }
}

Answer 1

您可能希望删除一些多余的文本/代码以澄清您的问题。花了一些时间找到重要的一点

我想一起摆脱用户输入。我该如何修改这个程序？

我假设这次事先创建了DATA1.txt，因为你不需要用户输入。您需要做的就是删除程序的前半部分，用户输入，然后更改行

file = new Scanner(new File(fileName + ".txt")); 到

file = new Scanner(new File("DATA1.txt"));

<强>代码

所以我刚开始删除了所有用户输入并更改了该行。

import javax.swing.*;
import java.io.*;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class CandyLand{
    public static void main(String str[]){
        Scanner file = null;
        ArrayList<Integer> list = new ArrayList<Integer>();

        try {
            file = new Scanner(new File("DATA1.txt"));
        }
        catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        while(file.hasNext()){
            if (file.hasNextInt())
                list.add(file.nextInt());
            else file.next();
        }
        try {
            DataOutput f2 = new DataOutputStream(new FileOutputStream("OUT1.txt"));
            for (Integer j: list){
                f2.writeBytes(j + ": ");
                for(int i=1; i<=j; i++){
                    f2.writeBytes("* ");
                }
                f2.writeBytes("\r\n");
            }
        }
        catch(Exception e){
            e.printStackTrace();
        }
    }
}

文本文件，删除用户输入

1 个答案: